Hypersensitivity to Lamotrigine and Nonaromatic Anticonvulsant Drugs: A Review

Lamotrigine and nonaromatic antiepileptic drugs (valproate, gabapentin, and topiramate) are associated with hypersensitivity reactions, mainly cutaneous eruptions. The underlying mechanisms of these manifestations are not yet completely understood. A cell-mediated pathogenic mechanism has been demonstrated in some cases on the basis of positive patch tests and/or lymphocyte transformation tests. Moreover, an in vitro lymphocyte toxicity assay, which exposes the patient's lymphocytes to arene oxides, has detected lymphocyte susceptibility to toxic metabolites in patients with hypersensitivity reactions to lamotrigine. Subjects with a history of mild hypersensitivity reactions and negative allergologic tests can be challenged with the suspected drugs. Challenge tests can also be useful to identify safe alternatives. Our study reports hypersensitivity reactions to lamotrigine and to nonaromatic antiepileptic drugs, especially those assessed by allergologic tests.